Ratio Calculator using PyQt5

In this article we will see how we can create a ratio calculator using PyQt5. Ratio is a contrast, which exists between two particular numbers, is defined as ratio. This ratio calculator is developed to compute this contrast and find out the relationship between these numbers. Below is how the calculator will look PyQt5 is cross-platform GUI toolkit, a set of python bindings for Qt v5. One can develop an interactive desktop application with so much ease because of the tools and simplicity provided by this library. Below is the command to install the PyQt5

pip install PyQt5

Concept : User has to select a ratio then enter another number for which calculator will find the corresponding ratio value, below is the formula used

A / B = C / X

Here A and B are the selected ratio and C is the entered number for which we have to find corresponding value of the ratio

GUI Implementation Steps : 1. Create a heading label that display the calculator name 2. Create three spin box for getting ‘A’, ‘B’ and ‘C’ values 3. Create labels between spin boxes for ratio and equal to symbol and label for showing ‘X’ value 4. Create push button for calculate the ratio value 5. Create a label to show the calculated value Back-End Implementation : 1. Set range to each of the spin box with minimum value equal to 1 so that user can’t enter 0 as input 2. Set various properties like alignment, geometry to each of the widget in the window 3. Add color effect to the push button 4. Add action to the push button when it get clicked 5. Inside the push button action calculate the value of ‘X’ according to the values entered by user 6. Remove decimal values if it is a whole number 7. Show the output with the help of result label

Below is the implementation 

Python3

# importing libraries
from PyQt5.QtWidgets import * from PyQt5 import QtCore, QtGui
from PyQt5.QtGui import * from PyQt5.QtCore import * import sys


class Window(QMainWindow):

    def __init__(self):
        super().__init__()

        # setting title
        self.setWindowTitle("Python ")

        # width of window
        self.w_width = 550

        # height of window
        self.w_height = 300

        # setting geometry
        self.setGeometry(100, 100, self.w_width, self.w_height)

        # calling method
        self.UiComponents()

        # showing all the widgets
        self.show()

    # method for components
    def UiComponents(self):

        # creating head label
        head = QLabel("Ratio Calculator", self)

        head.setWordWrap(True)

        # setting geometry to the head
        head.setGeometry(0, 10, 550, 60)

        # font
        font = QFont('Times', 15)
        font.setBold(True)
        font.setItalic(True)
        font.setUnderline(True)

        # setting font to the head
        head.setFont(font)

        # setting alignment of the head
        head.setAlignment(Qt.AlignCenter)

        # setting color effect to the head
        color = QGraphicsColorizeEffect(self)
        color.setColor(Qt.darkCyan)
        head.setGraphicsEffect(color)

        # creating a spin box
        self.a_spin = QSpinBox(self)

        # setting geometry
        self.a_spin.setGeometry(50, 90, 90, 35)

        # setting alignment
        self.a_spin.setAlignment(Qt.AlignCenter)

        # setting range
        self.a_spin.setRange(1, 999999)

        # creating a label
        l1 = QLabel(" : ", self)

        # setting geometry
        l1.setGeometry(140, 90, 30, 35)

        # setting alignment
        l1.setAlignment(Qt.AlignCenter)

        # creating a spin box
        self.b_spin = QSpinBox(self)

        # setting geometry
        self.b_spin.setGeometry(170, 90, 90, 35)

        # setting alignment
        self.b_spin.setAlignment(Qt.AlignCenter)

        # setting range
        self.b_spin.setRange(1, 999999)

        # creating a label
        l2 = QLabel(" = ", self)

        # setting geometry
        l2.setGeometry(260, 90, 30, 35)

        # setting alignment
        l2.setAlignment(Qt.AlignCenter)

        # creating a spin box
        self.c_spin = QSpinBox(self)

        # setting geometry
        self.c_spin.setGeometry(290, 90, 90, 35)

        # setting alignment
        self.c_spin.setAlignment(Qt.AlignCenter)

        # setting range
        self.c_spin.setRange(1, 999999)

        # creating a label
        l3 = QLabel(" : ", self)

        # setting geometry
        l3.setGeometry(380, 90, 20, 35)

        # setting alignment
        l3.setAlignment(Qt.AlignCenter)

        # creating a label
        lx = QLabel("X", self)

        # setting geometry
        lx.setGeometry(410, 90, 90, 35)

        # setting alignment
        lx.setAlignment(Qt.AlignCenter)

        # setting style sheet
        lx.setStyleSheet("QLabel"
                         "{"
                         "border : 1px solid black;"
                         "background-color : white;"
                         "font-size : 15px;"
                         "}")

        # creating a push button
        calculate = QPushButton("Calculate", self)

        # setting geometry to the push button
        calculate.setGeometry(175, 150, 200, 40)

        # adding action to the button
        calculate.clicked.connect(self.calculate)

        # adding color effect to the push button
        color = QGraphicsColorizeEffect()
        color.setColor(Qt.darkGreen)
        calculate.setGraphicsEffect(color)

        # creating a label to show result
        self.result = QLabel(self)

        # setting properties to result label
        self.result.setAlignment(Qt.AlignCenter)

        # setting geometry
        self.result.setGeometry(125, 210, 300, 60)

        # making it multi line
        self.result.setWordWrap(True)

        # setting stylesheet
        # adding border and background
        self.result.setStyleSheet("QLabel"
                                  "{"
                                  "border : 3px solid black;"
                                  "background : white;"
                                  "}")

        # setting font
        self.result.setFont(QFont('Arial', 11))


    def calculate(self):

        # getting spin box 'a' value
        a = self.a_spin.value()

        # getting spin box 'b' value
        b = self.b_spin.value()

        # getting spin box 'c value
        c = self.c_spin.value()

        # calculating 'x' value
        x = (c * b) / a

        # removing decimal if decimal is zero
        if x % 1 == 0:
            x = int(x)


        # setting text to the result label
        self.result.setText(str(a) + " : " + str(b) + " = "
                            + str(c) + " : " + str(x))





# create pyqt5 app
App = QApplication(sys.argv)

# create the instance of our Window
window = Window()

# start the app
sys.exit(App.exec())

Output :